Method of making an electromechanical personal care device

ABSTRACT

A method of making a handheld, electromechanical device useful in mammalian body-care includes the steps of: a) forming a one-piece housing having a single opening defined by a rim; b) assembling a unitary insert; c) inserting the unitary insert through the single opening of the housing; d) removably applying a cover having an exterior surface to close the opening of the one-piece housing; and e) attaching the unitary insert to at least one of the one-piece housing and the removable cover. The rim of the one-piece housing circumscribes a rim area, and the one-piece housing has a projected area that is substantially larger than the rim area. The unitary insert is dimensioned to be insertable through the opening defined by the rim, and it has a frame having disposed thereon electromechanical elements interconnected in an electrical circuit. The cover closes off the opening of the one-piece housing.

FIELD OF THE INVENTION

The present invention relates to a low-cost, handheld, electromechanicalpersonal body-care device having a one-piece housing and a unitaryinsert including a frame and electromechanical elements disposedthereon. The invention also relates to methods of making and assemblingthe devices and to kits containing interchangeable components of suchdevices.

BACKGROUND OF THE INVENTION

Handheld, electromechanical, personal body-care devices are known. Manyof these devices have mechanisms to transmit motion, such as vibration,rotation, oscillation, and the like, to a body surface, such as a humanface, elbows, and/or feet.

Hull, Jr. et al., U.S. Pat. No. 7,918,862, discloses a water-resistantdevice incorporating a switch assembly. This is a typical example of aninjection-molded clamshell housing that includes structural features topermit electromechanical elements to be mounted on the housing. In moredetail, the device includes a housing formed of a hard, lightweightplastic material, which may be formed of two portions and attached alonga seam. In addition to this seam between the housing portions,additional openings for a battery compartment and power switch areformed in the housing. Each of these openings employs a water-resistantseal.

Cowie et al., US Pat. Appl. No. 2010/0222719 purports to disclose afacial care appliance having a tubular body containing electromechanicalelements. The tubular body is formed of mating, inter-fittingsemi-cylindrical sidewalls and has outer skins disposed thereon. Thus,this body requires numerous seams to be sealed or gasketed if it is tobe used in wet environments to protect the internal electromechanicalelements.

Despite the teaching of the prior art, there is a continuing need forskin care devices that provide simple and reliable manufacture, reliableprotection against water damage, and potential for customization.

SUMMARY OF THE INVENTION

Therefore, we have discovered that separating the housing and theelectromechanical elements of a handheld personal body-care deviceincreases manufacturing flexibility, reduces manufacturing costs, andreduces potential for the undesired ingress of liquids.

In particular, a method of making a handheld, electromechanical deviceuseful in mammalian body-care includes the steps of: a) forming aone-piece housing having a single opening defined by a rim; b)assembling a unitary insert; c) inserting the unitary insert through thesingle opening of the housing; d) removably applying a cover having anexterior surface to close the opening of the one-piece housing; and e)attaching the unitary insert to at least one of the one-piece housingand the removable cover. The rim of the one-piece housing circumscribesa rim area, and the one-piece housing has a projected area that issubstantially larger than the rim area. The unitary insert isdimensioned to be insertable through the opening defined by the rim, andit has a frame having disposed thereon electromechanical elementsinterconnected in an electrical circuit. The cover closes off theopening of the one-piece housing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of the device of thepresent invention.

FIG. 2 is a side elevation of the housing of FIG. 1.

FIG. 3 is a top view of the housing of FIG. 1 showing the projected areaof the housing.

FIG. 4 is an exploded, side elevation of the device of FIG. 1.

FIG. 5 is a detailed view of the unitary insert of FIGS. 1 and 4.

FIG. 6 is an exploded, side elevation of an alternative embodimenthaving a unitary insert with a modified distal end.

FIG. 7 is a perspective view of the cover and housing/insert of FIGS.1-5 with the cover separated from the housing/insert and rotated to showthe underside of the cover.

FIG. 8 is an exploded, perspective view of the cover and housing of anembodiment of the present invention having a cover in the form of aplug.

FIG. 9 is a partial cross-section of an embodiment of the presentinvention having a shaft disposed through the cover.

FIG. 10 is a partial cross-section of the housing and insert of anembodiment of the present invention having a gasket disposed between theinsert and the housing.

FIG. 11 is a side elevation of a preform useful in blow-molding theone-piece housing of FIG. 2.

FIG. 12 is a schematic view of components of a kit comprising multipleunitary inserts and one-piece housings according to an embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A review of the prior art described above suggests that elegant, simplesolutions to water resistant electromechanical personal body-caredevices are still needed. In particular, plastic housings are oftentwo-piece, injection-molded clam shell structures. This provides ease inmanufacturing with structural elements extending from the interiorsurface of the housing that form mounting surfaces for electromechanicalelements contained therein. However, as the electromechanical elementsare changed during the evolution of a commercial product, either theinjection mold must be modified, or there are significant structurallimitations on the design evolution. Alternatively, changes in thehousing must be designed in conjunction with the mounting of theelectromechanical elements. In addition, mounting electromechanicalelements directly on the housing provides direct pathways to transferundesired motion to the gripping surfaces of the housing. Finally,combining multiple plastic pieces together to form a unitary housingrequires additional locations to seal the structure from the possibleingress of liquids, such as water.

Therefore, we have separated the housing and the electromechanicalelements to increase manufacturing flexibility, reduce manufacturingcosts, and to reduce potential for the undesired ingress of liquids. Inparticular, we have invented a low-cost, handheld, water-resistantelectromechanical, personal body-care device that has a one-piecehousing and a single opening defined by a rim, a unitary insertdimensioned to be insertable through the opening, and a removable coverarranged and configured to engage the rim. The unitary insert includes aframe having disposed thereon electromechanical elements interconnectedin an electrical circuit. The removable cover has an exterior surface,and it is arranged and configured to transmit at least one output of theelectromechanical elements disposed within the housing.

As used herein the specification and the claims, the term “unitary” andvariants thereof means a collection of parts joined to form a whole.

As used herein the specification and the claims, the term “rim” andvariants thereof means the edge of a structure defining an opening,which may be circular or other geometric shape.

As used herein the specification and the claims, the term “projectedarea” and variants thereof means the area of the projection of athree-dimensional object onto a plane. When two or more projected areasare compared, the projection is onto the same plane.

As used herein the specification and the claims, the term “removablecover” and variants thereof relates to covers that are designed to beapplied to close the opening of the one-piece housing and to beremovable therefrom without undue effort and/or damage to any of thecover, unitary insert, and one-piece housing.

As shown in FIG. 1, a first embodiment of the device of the presentinvention is a handheld, water-resistant electromechanical device 10useful in mammalian personal body-care. The device includes a one-piecehousing 20 containing a unitary insert 30 and having a cover 40.Preferably, the one-piece housing 20, the unitary insert 30, and thecover 40 are arranged and configured to resist the ingress of liquidsinto the device. This may be done by selective use of gaskets, asdescribed below. Thus, the device can better resist the ingress ofliquids into the device. In addition, the unitary insert 30 is attachedto at least one of the one-piece housing 20 and the cover 40 to providea more robust device.

As shown in FIG. 2, the one-piece housing 20 defines a volume containedby the housing, and it has a single opening 21 defined by a rim 22. Theone-piece housing preferably has an ergonomic shape that facilitatesholding by a human hand. The handheld electromechanical device islight-weight to prevent user fatigue during use. Preferably, thehandheld, electromechanical device has a mass of less than about 450grams; more preferably, less than about 300 g; and most preferably, lessthan about 150 g. The one-piece housing 20 has a substantiallycontinuous exterior wall to provide a pleasing appearance and toeliminate the risk of poorly closed seams between housing componentspresent in multi-part housings that can provide pathways for the ingressof liquids into the device. The single opening greatly reduces thenumber of and linear dimension(s) of seams in the construction of theelectromechanical device. It may be desirable to provide a shoulder 23proximate the opening 21. Thus, the rim 22 can extend from the shoulder23 to permit the cover 40 to engage and fit over the rim 22 in thisembodiment. A gasket 24 may be disposed about the rim 22. As shown inFIGS. 2 and 10, the gasket 24 is an o-ring, and it is disposed in agroove 25 dimensioned to provide an effective, sealing seat for thegasket 24 to prevent the ingress of liquids into the device 10. While acircular opening and corresponding rim are shown in FIGS. 1-5, it willbe recognized that alternative geometric shapes are possible.

The one-piece housing 20 preferably has an interior surface that issubstantially smoothly continuous for ease of manufacture and forimproved mechanical isolation of the unitary insert 30 from the housing20. This smooth, continuous interior surface also necessitates assemblyof electromechanical elements on the frame of the unitary insert, asdiscussed in greater detail, below. As shown in FIG. 3, the one-piecehousing 20 has a projected area PA_(H) (shown by cross-hatching withinbold outside line defining the periphery of the projection) that issubstantially larger than the rim area RA (shown by oppositecross-hatching within the opening), the area circumscribed by the rim22. In this embodiment, the projected area PA is symmetrical on oppositesides of a plane perpendicular to the rim 22, although it is notradially symmetrical about the center of the rim 22. In alternativeembodiments, the projected area may be radially symmetrical about acenter of the opening 21, symmetrical across multiple planesperpendicular to the rim, or it may be isotropic (having a structureindependent of the direction from the center or diameter of theopening).

The outer surface of the one-piece housing may be smooth or it may havesurface features, such as highlighted gripping area 26. The surfacefeatures may be formed during the formation of the one-piece housing orthey may be added later. These surface features may include withoutlimitation, texturing, coloring, information, etc. The surface featuresmay be provided through known methods, such as by coating (e.g.,printing, and/or painting), applying labels or other structures,etching, dyeing, and the like. Texturing may be slight or it may besubstantial enough to be noticeable on the interior surface of thehousing. The one-piece housing can be transparent in order to be able tosee the internals. This is useful for using LED's internally as statusindicators. Housing 20 is preferably rigid, although it may be helpfulto have one or more flexible portions. Alternatively, the one-piecehousing may be more flexible. The partial or complete flexibility may beuseful to incorporate a switch that the user can depress by flexing thehousing (same applies for the cap) or having a pump for dispensingliquids therethrough. Gaskets protect the ingress of liquids from theexterior, but in another embodiment can be used to protect liquids fromexiting.

FIG. 4 shows an exploded, side elevation of the device of FIG. 1 to showthe relationship between the one-piece housing 20, the unitary insert30, and the cover 40, and FIG. 5 provides additional details of theunitary insert 30 and its constituent elements. Again, the unitaryinsert 30 includes a frame 31 having disposed thereon electromechanicalelements interconnected in an electrical circuit. The frame 31 has aproximal portion 32 and a distal portion 33 disposed opposite thereof. Aflange 34 or other attachment surface is at the proximal end 32 toattach to or to engage with the rim 22 or other portion of the housing20 near the opening 21 to secure the unitary insert 30 to the housing20. The electromechanical elements are mounted on or disposed withinrecesses in the frame 31. For example, in the embodiment shown in FIGS.4 and 5, the insert 30 includes an electric motor 35 and a power sourcesuch as a battery 36 interconnected, e.g., with wires or otherelectrical conduits, in an electrical circuit. The circuit may be openedand closed by means of a switch, elements of which may be located on thecover, as discussed in further detail, below.

The unitary insert 30 is dimensioned to be insertable through theopening 21 and to be substantially contained within the one-piecehousing 20. In the embodiment of FIGS. 1-5, the unitary insert 30 has aprojected area PA_(I) that is circumscribed by the rim 22 (see FIG. 4).It should be noted that this projected area does not include any portionof the mounting flange 34 that is to be secured to the rim 22 through aninterference fit or by overlapping with a portion of the rim 22. Inother words, the unitary insert 30 is insertable into the opening 21with a single, linear motion without interference. In an alternativeembodiment shown in FIG. 6, the unitary insert 30′ has a projected areaPA_(I)′ that extends outside of the opening due to a lateral extensionof a distal portion 33′. This unitary insert 30′ is insertable into theopening 21 by first inserting the distal portion 33′ through the opening21, pivoting the unitary insert 30′ to align a remaining portion of theunitary insert that has a projected area that is circumscribed by therim, and inserting the remaining portion of the unitary insert 30′through the rim 21.

The removable cover 40 engages the rim 22 to close the opening 21. Inthe embodiment of FIGS. 1-5, the removable cover 40 is a cap that isarranged and configured for removable engagement over the rim 22. Thecap also engages the gasket 24 disposed about the rim 22 to prevent theingress of liquids into the device 10. This sealing engagement protectsthe electromechanical elements from damage, including short-circuiting,that water or other liquids may cause if it were to penetrate into theinterior of the housing 20. In the embodiment of FIGS. 1-5 and 7 andalso in the embodiment of FIG. 10, discussed in greater detail, below,the cap has an inner surface 41 disposed toward the unitary insert 30that closes the opening 21, and an exterior surface 42 disposed awayfrom the opening 21. In addition, the cap has sidewalls 43 that encirclethe rim 22 and engage the gasket 24. The exterior surface 42 may itselfbe a body-care surface, or it may be a platform or other structure onwhich optional, body-care elements, 44 may be disposed, either directlyon the exterior surface 42 or through an optional coupler 44 a such asdisclosed in commonly assigned, Hull, U.S. Ser. No. 12/770,994, filedApr. 30, 2010. Such optional, body-care element may be applied directlyon the optional coupler 44 a or onto the exterior surface, or there maybe an attachment mechanism, such as a hook-and-loop system, oradhesives, clamps, snaps, and the like.

In the preferred embodiment show in FIGS. 1-5, the cover cooperates withthe insert to form a switch. This is shown in more detail in FIG. 7. Theunitary insert 30 has a first electrical conductor 37 a disposed on itsproximal surface 32 a, and the inner surface 41 of the cap has a secondelectrical conductor 37 b. The cap is preferably engaged with the rim 22via a bayonet connector mechanism with one or more pins disposed on theframe and matching “L” slots disposed in the inner walls 43 of the cap.The cap and/or rim are formed of a sufficiently resilient material topermit the cap and rim to be removable locked together. In thisembodiment, the “L” slot is extended to permit the cap to rotate between(1) an “on” position in which the second electrical conductor 37 b onthe cap connects the first electrical conductor 37 a disposed on theproximal surface 32 a of the unitary insert 30 and the battery 36 toclose the electrical circuit and (2) an “off” position in which thesecond electrical conductor 37 b on the cap is rotated to break theelectrical circuit by disengaging either or both of the first electricalconductor 37 a on the unitary insert 30 and battery 36.

Although the previous paragraph described a bayonet coupling between thecover 40 and insert 30, the elements of the bayonet coupling such as thepins and slots can be located on combinations of housing 20, the unitaryinsert 30, and the cover 40.

Another embodiment may replace the rotating switch formed by thecombination of the cover 40 and the insert 30 with a push-button switchoperated by flexing the housing and/or cover.

In an alternative embodiment shown in FIG. 8, the cover is a plug 40′that is arranged and configured for removable engagement within the rim22′. A gasket 45 such as an o-ring may be disposed about the plug 40′.Again, the o-ring may be disposed in a groove dimensioned to provide aneffective, sealing seat for the gasket 45 to prevent the ingress ofliquids into the device 10.

In a further alternative embodiment shown in FIG. 9, the cover 40″ mayhave an aperture 46 having a shaft gasket 47 and a moveable shaft 48disposed therein, and wherein the moveable shaft 48 is operativelyconnected to the motor 35 mounted on the insert to transfer motion fromthe motor 35 to a moving platform 49 having body-care element 44disposed thereon outside of the housing 20. Thus, the body-care element44 may rotate or oscillate against the user's skin. Other motion outputsare also possible. For example, cams, slides, and/or other translationalmechanisms may interact with the moving platform 49.

As mentioned above, it is desirable to construct the body-care device 10to resist the ingress of liquids into the device to avoid damage to theelectrical components contained therein. Thus, the housing 20 sealinglyengages with at least one of the unitary insert 30 and cover 40. The useof one or more gaskets 24, 45 between the cover 40 and the housing 20are described above. In addition or in place of such gaskets, it may bedesirable to seal the connection between the housing 20 and the unitaryinsert 30. Thus, an appropriate gasket 38 may be disposed between thehousing 20 and the unitary insert 30, as shown in FIG. 10. This gasket38 may simply resist the ingress of liquids into the interior of thehousing 20, or it may also act as a damping member to dampen movementgenerated by the electromechanical elements disposed on the frame 31 andisolate it from transfer to the housing 20. However, if one determinesthat water-resistance is not critical to the operation of the device,one or more of the gaskets can be eliminated.

As can be seen in a review of the foregoing paragraphs, cover 40 isarranged and configured to transmit at least one output of theelectromechanical elements disposed within the housing. For example, inthe embodiment of FIGS. 1-5, vibratory motions from the insert 30 may betransferred through the cover 40 to the exterior surface 42. In theembodiment of FIG. 9, rotating or oscillating motion from the insert maybe transferred through the cover 40″ via moveable shaft 48 to askin-contacting element 48. In the embodiment of FIG. 10, the vibratorymotions from the insert 30 may be isolated from the housing 20 andtransferred directly to a skin-contacting element 48.

As discussed above, the one-piece housing 20 defines a volume containedby the housing. When the opening 21 is closed by the cover 40, thevolume contained by the one-piece housing is at least about 60% of thetotal volume contained by the one-piece housing 20 and the cover 40.Preferably, the volume contained by the one-piece housing is at leastabout 80%, and more preferably at least about 90% of the total volumecontained by the one-piece housing 20 and the cover 40.

The device of the present invention is made by forming a one-piecehousing, assembling a unitary insert, inserting the unitary insert intothe housing, attaching the unitary insert to the one-piece housing, andremovably applying a cover to the housing. Again, the one-piece housingdefines a volume and has a single opening defined by a rim. The housingalso has a substantially continuous exterior wall, and it has aprojected area that is substantially larger than the rim. Preferably,the housing has a shoulder, and the rim extends above the shoulder. Therim may also have a gasket disposed thereabout. Thus, the device may bemade by forming a one-piece housing having an opening defined by a rimand arranging a gasket about the rim.

The one-piece housing may be formed by blow-molding a thermoplasticpreform to the desired final form. Those of ordinary skill in the artwill recognize how to design the preform dimensions to result in thedesired final form. For example, the one-piece housing 20 shown in FIG.2 may result from blow-molding a thermoplastic preform 50 shown in FIG.11. The preform 50 has elements of the rim 22, such as the groove 25,already molded into it. These elements are maintained during theblow-molding process.

The blow-molding process provides a one-piece housing having asubstantially continuous exterior wall with an interior surface that issubstantially smoothly continuous. Alternative molding processes includerotomolding. Again, these processes permit the formation of finalhousing shapes in which the projected area PA is symmetrical on oppositesides of one or more planes perpendicular to the rim 22, symmetricalabout a center of the opening 21, and/or isotropic. In marked contrastto injection molding, the blow-molding process also permits the simpleformation of desired one-piece housings having a projected area that issubstantially larger than the rim. In cases in which the one-piecehousing material is subjected to conditions that may potentially alterthe dimensions of the opening and/or rim—structures that are significantto sealing engagement of the components of the device—it may be usefulto incorporate structures to maintain these dimensions during themanufacturing process. For example, the process equipment may includeelements that maintain the diameter of the rim after the formation ofthe preform, during the blow-molding process, and during a cool-downperiod after the one-piece housing is complete.

The unitary insert again includes a frame having disposed thereonelectromechanical elements interconnected in an electrical circuit. Theframe may be formed of one or more structural elements, preferablyplastic, that may be formed by any means available. For example, one ormore elements of the frame may be injection molded plastic componentsthat form mounting surfaces for a motor or other motion-generatingdevices, a battery or other power sources, gears, shafts, etc. The framemay also have disposed thereon electrical connectors and one or moreswitches or switch elements. The individual components of the unitaryinsert are joined together to form the complete unitary insert. This isinserted through the single opening of the housing and attached thereto.As discussed above, the unitary insert 30 (such as shown in FIG. 4) maybe inserted into the one-piece housing 20 using a single, linear motion.Alternatively, as shown in FIG. 6, the method may require that a distalportion 33′ of the unitary insert be aligned with the opening, insertingthe distal portion through the opening, pivoting the unitary insert toalign a remaining portion of the unitary insert that has a projectedarea that is circumscribed by the rim, and inserting the remainingportion of the unitary insert through the rim.

Optionally, a gasket and/or damping member may be disposed between theunitary insert and the housing to further protect the electromechanicalelements from the ingress of liquids and/or to inhibit the transfer ofmotion between the unitary insert and the housing.

The method also includes removably applying a cover to the housing tocover the opening thereof. In one embodiment, the cover is a cap, andthe step of removably applying the cover comprises removably engagingthe cap over the rim. In another embodiment, the cover is a plug, andthe step of removably applying the cover comprises removably engagingthe plug within the rim. If the cover is a plug, the method may includethe step of arranging a gasket about the plug.

The unitary insert 30 is attached to at least one of the one-piecehousing 20 and the cover 40 to provide a more robust device. Theattachment may be permanent or it can be temporary or detachable. Theattachment can be done through known methods including withoutlimitation, welding, adhesives, and mechanically fastening (screw, snap,interference fit, and the like). In several preferred embodiments, theunitary insert is ultrasonically welded to either the cover or theone-piece housing.

The devices of the present invention can be used for any desiredbody-care regimen. Known regimens include cleansing, exfoliating,microdermabrasion, massage, and the like. In embodiments incorporatingoptional body-care elements, a user may select an appropriate body-careelement, apply it to the exterior surface of the cover, apply water tothe body-care element (if appropriate), activate the motion of thedevice, and apply the body-care element to desired locations. After use,the body-care element may be removed and discarded. Thus, the body-careelements may be in the form of pads, brushes, sponges, poufs (gatherednets of polymeric material), protrusions (for massaging, etc.), and thelike.

Another method of the present invention relates to a method of makinghandheld electromechanical devices and/or permitting a user to selectcomponents of a handheld mechanical device body-care system. The methodincludes the steps of forming a one-piece housing defining a volume andhaving a single opening defined by a rim, selecting a unitary insertdimensioned to be insertable through the opening defined by the rim froma plurality of unitary inserts, inserting the selected unitary insertthrough the single opening of the housing and attaching the insert tothe one-piece housing, selecting, from a plurality of covers, a coverarranged and configured to cooperate with the selected unitary insert,and removably applying the cover to close the single opening of thehousing. Each of the plurality of unitary inserts includes a framehaving disposed thereon electromechanical elements interconnected in anelectrical circuit. Each of the plurality of different covers isarranged and configured to cooperate with one or more of the pluralityof different unitary inserts.

The one-piece housing may be of any shape, or selected from among aplurality of shapes and sizes and surface features, as long as it issuitable for handheld, consumer use. Additionally, the plurality ofunitary inserts may be selected from a supply of unitary inserts havingdifferent electromechanical elements, sizes, and/or shapes. Thus, thedesired unitary insert may provide different motion, different powerlevels, and other different properties, as desired by consumers. Theplurality of covers may be selected from a supply that are arranged andconfigured to cooperate with the various one-piece housings and unitaryinserts. These covers may be caps, plugs, and the like, as describedabove.

Therefore, this method provides flexibility for manufacturers to providecustomizable and/or a variety of handheld electromechanical devices on asingle manufacturing line. Alternatively, it permits the creation ofkits of body-care devices and inter-changeable elements for consumers tohave a variety of customizable configurations in their homes.

As described above, at least two of the one-piece housing, unitaryinsert, and cover are preferably sealing engaged to resist the ingressof liquids into the one-piece housing. This may be achieved by arranginga gasket about the rim, about the cover, and/or between the unitaryinsert and the one-piece housing. In addition, the damping memberdescribed above may be provided between the unitary insert and theone-piece housing.

The kit having interchangeable components includes a first componentthat is a one-piece housing, a second component that is a unitaryinsert, and a third component that is a cover. The kit includes at leastone of each of the first, second, and third components, and at least twoof one of the components. Thus, the kit may include one one-piecehousing and multiple unitary inserts and corresponding covers, or thekit may include one unitary insert and multiple one-piece housings andcorresponding covers. While it may also be possible to have one coverand multiple one-piece housings and unitary inserts, this is likely tobe rather uncommon. Finally, the kit may include a plurality of each ofthe three components.

An example of a kit is shown in FIG. 12. The kit contains two unitaryinserts 101, 102. Each unitary insert 101, 102 has associated therewitha cover 103, 104, respectively. The combination unitary insert/cover canbe combined with one of four one-piece housings 105, 106, 107, 108(shown in phantom cross-section). However, unitary insert 101 has alateral extension 109 on its distal end, and this extension interfereswith the two of the one-piece housings. Therefore, this unitary insert101 can be used only with one-piece housings 105, 107 and not withone-piece housings 108, 109 (as indicated by the arrows connecting theunitary insert and housings).

The specification and embodiments above are presented to aid in thecomplete and non-limiting understanding of the invention disclosedherein. Since many variations and embodiments of the invention can bemade without departing from its spirit and scope, the invention residesin the claims hereinafter appended.

The invention claimed is:
 1. A method of making a handheld,electromechanical device useful in mammalian body-care, the methodcomprising: a) providing a one-piece housing having a continuous,seamless exterior wall with a single opening defined by a rim, whereinthe rim circumscribes a rim area, and the one-piece housing has aprojected area that is substantially larger than the rim area; b)providing a unitary insert dimensioned to be insertable through theopening defined by the rim, the unitary insert comprising a frame havingdisposed thereon electromechanical elements interconnected in anelectrical circuit; c) inserting the unitary insert through the singleopening of the one-piece housing; d) removably applying a cover havingan exterior surface to close the opening of the one-piece housing; ande) attaching the unitary insert to at least one of the one-piece housingand the removable cover.
 2. The method of claim 1, further comprisingthe step of sealingly engaging at least two of the cover, frame andone-piece unitary housing to resist the ingress of liquids into theone-piece housing.
 3. The method of claim 1, wherein the one-piecehousing has a shoulder, and the rim extends from the shoulder.
 4. Themethod of claim 3, further comprising the step of arranging a gasketabout the rim.
 5. The method of claim 1, wherein the step of forming aone-piece housing comprises subjecting a thermoplastic preform to ablow-molding process to form the one-piece housing.
 6. The method claim1, wherein the step of forming a one-piece housing comprises rotomoldinga polymeric material to form the one-piece housing.
 7. The method ofclaim 1, wherein the one-piece housing has a projected area that issymmetrical on opposite sides of a plane perpendicular to the rim. 8.The method of claim 1, wherein the unitary insert has a projected areathat is circumscribed by the rim, and inserting the unitary insertthrough the single opening involves a single, linear motion.
 9. Themethod of claim 1, wherein the unitary insert has a projected area thatextends outside of the opening, and inserting the unitary insert throughthe single opening comprises aligning a distal portion of the unitaryinsert with the opening, inserting the distal portion through theopening, pivoting the unitary insert to align a remaining portion of theunitary insert that has a projected area that is circumscribed by therim, and inserting the remaining portion of the unitary insert throughthe rim.
 10. The method of claim 1, further comprising providing adamping member between the unitary insert and the one-piece housing toinhibit the transfer of motion therebetween.
 11. The method of claim 1,wherein the removable cover is arranged and configured to transmit atleast one output of the electromechanical elements disposed within theone-piece housing through the exterior surface of the cover.
 12. Themethod of claim 11, wherein the cover further comprises an aperturehaving a gasket and a moveable shaft disposed therein, and wherein themoveable shaft is operatively connected to the motor to transfer motionfrom the motor to a skin-contacting element disposed outside of theone-piece housing.
 13. The method of claim 1, wherein the removablecover comprises a cap, and the step of removably applying the covercomprises removably engaging the cap over the rim.
 14. The method ofclaim 1, wherein the removable cover comprises a plug, and the step ofremovably applying the cover comprises removably engaging the plugwithin the rim.
 15. The method of claim 14, further comprising arranginga gasket about the plug.
 16. The method of claim 1, further comprisingarranging a gasket about the unitary insert between the unitary insertand the one-piece housing.
 17. The method of claim 1, further comprisingproviding surface features on an outer surface of the one-piece housing.18. The method of claim 1, wherein attaching the unitary insertcomprises attaching the unitary insert to the one-piece housing afterinserting the unitary insert through the opening.
 19. A method of makinga handheld, electromechanical device useful in mamalian body-care, themethod comprising: a) forming a one-piece housing having a singleopening defined by a rim, wherein the rim circumscribes a rim area, andthe one-piece housing has a projected area that is substantially largerthan the rim area; b) assembling a unitary insert dimensioned to beinsertable through the opening defined by the rim, the unitary insertcomprising a frame having disposed thereon electromechanical elementsinterconnected in an electrical circuit; c) inserting the unitary insertthrough the single opening of the housing; d) removeably applying acover having an exterior surface to close the opening of the one-piecehousing; and e) attaching the unitary insert to the cover prior toremovably applying the cover to close the opening.
 20. A method ofmaking a handheld, electromechanical device useful in mammalianbody-care, the method comprising: a) inserting a unitary insert througha single opening of a one-piece housing; b) removably applying a coverhaving an exterior surface to close the opening of the one-piecehousing; and c) attaching the unitary insert to at least one of theone-piece housing and the removable cover so that said unitary insert ismechanically isolated from the one-piece housing to reduce transfer ofundesired motion to the gripping surfaces of the one-piece housing;wherein: the one-piece is formed to have a continuous, seamless exteriorwall with a single opening defined by a rim circumscribing a rim areaand a projected area that is substantially larger than the rim area; theunitary insert is dimensioned to be insertable through the openingdefined by the rim; and the unitary insert is assembled by mounting on aframe the electromechanical elements of said electromechanical deviceinterconnected in an electrical circuit to form a complete unitaryinsert.
 21. The method of claim 20, wherein the one-piece housing isformed to have an interior surface that is substantially smoothlycontinuous so that the electromechanical elements are only mounted onthe frame and cannot be mounted on the interior surface of the one-piecehousing.